514 
PROFESSOR W. N. HARTLEY ON THE 
probably be evident in the absorption spectrum of the alkaloids. There are, however, 
two conditions under which an aromatic derivative would certainly not affect the 
spectrum in a characteristic manner, and these are, when the acid is a hydrogenised 
body like hyclrophthalic acid, or when the basic portion of the molecule has so power¬ 
fully absorbed the rays that the band of selective absorption is obscured. The 
spectrum of narceine is undoubtedly of this character, and so likewise is that of 
oxynarcotine. In order to comment upon the nature of the various absorption 
spectra described, it will be advantageous to refer briefly to what is at present known 
concerning the constitution of some of the alkaloids. 
Alkaloids may be divided into two groups: (a) those which exhibit spectra with 
absorption bands; and (5) those which transmit continuous spectra. 
Alkaloids and derivatives exhibiting spectra with absorption bands. 
Aconitine 
Pseudaconitine 
Japaconitine 
Morphine 
Narcotine 
Codeine 
Thebaine 
Papaverine 
Oxynarcotine 
Apomorphine-hydrochloride 
Tetra-acetyl-morph ine 
Di-acetyl-codeine 
Quinine 
Qu inine-sulphate 
Cinchonine-sulphate 
Quinidine-sulphate 
Cinchonidine-sulphate 
Veratrine 
Pipeline 
Brucine 
Strychnine 
Alkaloids yielding continuous spectra. 
Narceine Solamine Picrotoxine 
Aconitine (foreign) Hyoscyamine Nicotine 
Cevadine Digitaline Caffeine 
Atropine 
The properties of the aconitines. 
By saponifying the aconitines with acids, alkalies, or even with water at a high 
temperature under pressure, aconitine, japaconitine, and picraconitine yield benzoic 
acid and a new base, while pseudaconitine furnishes di-methyl-protocatechuic acid 
C fi Hoi (^^^- 3)2 Jt W as thought probable that by the action of bromine on the 
alkaloids substitution would occur in the benzene nucleus, and a definite absorption 
of a pronounced character would result. This was however not the case, probably 
because the alkaloids were altogether altered, for after treatment they exhibited no 
absorption bands. In comparing the diagrams it is interesting to note the difference 
between pseudaconitine and the other aconitine bases, it evidently possesses a nucleus 
with a similar constitution, but the acid residue which is different modifies the absorp¬ 
tion curve. 
